HBO's string of hard-hitting, insightful documentaries continues with Witness, a 4-part series that focuses on war photography from the viewpoint of the person behind the camera. What's it like to be a journalist and balance that role with being a compassionate human being who is a witness to death and destruction? The series goes into the frontlines in Mexico, Libya, South Sudan, and Brazil to give an up-close, personal look into the lives of people who sometimes get way too close to their subjects, putting their lives in constant jeopardy.